that's so cute!

i have only played with it a little bit and no errors so far for me on lubuntu.
i look forward to using this with some of my blender animations.

thanks you so much for showing us the awesomeness of your gem engine and sharing all your hard work.. you are the best!

so you can't see the patch because the gemwin is to big? and when you render it covers the patch.... is that what you mean.

have a look at pdmtl abstractions
https://wikifarm.koumbit.net/dataflow/PdMtlAbstractions

then look in the gems and find gems.multi.crop
ta-o